Character's level up sequence at character home screen.

Hi,

I was playing around at character screen/creation and noticed you can level up. As I like to explore everything I leveled up all pregen characters. However I noticed you can't reset them and now I can't select any for the campaign because they are level 2.

Is there away to undo the level up at the start? Also I leveled up a custom made character and can't use it, shame as I had a very good dice roll :-(
It would be nice if you can reset a character back to level 1.

Cheers
Jerry